1. Field of Invention
The present invention generally relates to an apparatus and method for automatically leveling objects such as; paintings, photographs, documents, mirrors, and the like, that are suspended or hung from a mounting point on an even or uneven reference plane, and more specifically, to an automatic leveling apparatus having a shift lever assembly that automatically adjusts the inclination angle of a suspended or hung object to a level position, as determined under the influence of gravity, by way of a pendulum actuated switch.
2. Prior Art
People tend to display various objects for different purposes, such as; showing off their treasured photographs and paintings, displaying official documents including certificates, permits, and diplomas, or simply to adorn their bare walls. These objects are usually suspended from a mounting point on a vertical wall within a frame or other enclosing structure. The suspended object requires initial orientation and leveling to achieve a symmetric position with respect to a reference plane, and recurrent leveling to maintain said orientation. Accordingly, this reference plane principally refers to a ninety-degree angle to a wall of a house or building; wherein, most are constructed and raised in a vertical manner. Visual inspection from a distance is the most common way to judge whether an object suspended from a mounting point has a level orientation. Direct human intervention is the ordinary and simple, if not biased, approach to bringing an object back to level or its original orientation. The foregoing unassisted manual method of leveling an object suspended from a mounting point provides an inconsistent estimation and may require more than one person and multiple attempts to complete the course. Thusly, various apparatuses and methods have been disclosed in prior art, addressing the intricacy of leveling an object suspended from a mounting point using manual means and thereafter providing automatic leveling features as set forth hereunder, to wit:
U.S. Pat. No. 7,216,841, issued on May 15, 2007 to Dodig, provides a method and apparatus for hanging pictures and other wall objects using a fastening device having a clear, flexible, non-resilient carrier having at least two mounting hooks in parallel alignment, which are secured to the carrier for engaging wire mounting means on the back of the picture or wall object. Said carrier may include a leveling device, preferably a bubble level. This leveling device may be removably attached to the carrier by means of a snap or compression fit within a concavity or depression in the carrier to thereby allow repeated uses of the same leveling device.
U.S. Pat. No. 4,883,247, issued on Nov. 28, 1989 to Crandall, discloses a picture hanger and method of using the same for readily hanging articles in level manner. This hanger having a built-in leveling device will continue to remain level irrespective of any vibrations that may occur to the wall on which it may be mounted.
Among other various automatic leveling apparatuses and related methods existing in the prior art, only two (2) references are deemed relevant to the present invention. These are:                a) U.S. Publication No. 20060278799, published on 14 Dec. 2006 to Newman, involves a frame leveler wherein a pivotable, weighted bob is used as a gravity reference to control a lock that unlocks the extension of a cable on the side of a frame that is tilted up with respect to the other side, when the frame is not level. The extensible cable is let out until the frame is once again level, at which point the extensible cable is locked and prevented from extending further. When the frame side is titled down with respect to the other side, or the frame is level, the extensible cable is locked and prevented from extending on that side, and        b) U.S. Publication No. 20070214669, published on 20 Sep. 2007 to Van Luchene and Mueller, pertaining to an automated leveling apparatus wherein when it is mounted to the lower right corner of the frame or other object, the apparatus is activated whenever the frame or object becomes misaligned. When either corner is lowered, the integral Tilt switch “senses” this misalignment and an electrical circuit is created or closed. This electrical circuit, in turn, supplies power to a DC motor, which causes the DC motor to turn, which then turns a gear that is further attached to a wheel. This wheel is positioned in the apparatus such that, when attached to the frame, the wheel will come in direct contact with the adjacent wall or other stationary mounting object. When the wheel turns, the frame is moved at the corner where the device is attached, thereby aligning the frame or object.        
However, the aforementioned prior art references have certain limitations, disadvantages and design inconsistencies that need to be remedied.
With regard to the first relevant automatic leveling apparatus prior art reference, the frame leveler; the limitations, disadvantages and design inconsistencies as follows:                a) The weight of the bobs used in the gravity reference must be matched to the object to be leveled. Specifically, the bob's need to be adequate to counter the weight of the frame in order to facilitate leveling, without surpassing the weight that the frame can counter in the leveling process. This increases design complexity and, depending on the size and overall weight of the frame to be leveled, said comparable set of bobs can make the apparatus bulky and an impractical attachment to the back of a frame whose object is to rest near perpendicular against a flat surface.        b) Moreover, the mounting procedure for frame leveler is quite complex. One has to identify certain portions of the frame to mount the different parts of the frame leveler.        c) Finally, the frame leveler can only deploy the extensible cable on the high side of the hanging object until the reel containing said cable is fully extended. Once the reel is fully deployed, the frame leveler loses its ability to automatically level. Resultantly, human intervention is necessary to lift the weight of the frame off the leveling mechanism so that the cable that suspends the frame can retract back into its reel, restoring the devices ability to level misaligned objects.        
Referring to the second relevant prior art referenced, the automated leveling apparatus, the limitations, disadvantages and design inconsistencies as follows:                a) For the automated leveling apparatus to work, the misaligned object should be completely resting/leaning on a generally solid, unmovable, and flat plane or object;        b) The automated leveling apparatus should include a material that will aid in generating traction or friction to work, thus, entails additional cost and complexity;        c) The gliding of the wheels of the automated leveling apparatus may cause undesirable marks on the surface. Accordingly, a support device or glide button is needed. This device may be made of any suitable material that will balance the hanging object properly while substantially offsetting the width of the installed apparatus. This again entails additional system cost and mounting complexity;        d) To function properly, the individual parts of the automated leveling apparatus must be installed on specific areas of the hanging object to be leveled, based on the size and weight of the hanging object, thus making the installation complicated and burdensome;        e) To alert the user that it is operating, the installation of a buzzer or Light Emitting Diode (LED) on the automated leveling apparatus is necessary;        f) The motor, gear, and wheel of the automated leveling apparatus turn in one direction if the tilt is on the right side and the opposite direction if the tilt is on the left side in order to realign the misaligned object. This necessitates either two motors, or a single motor that operates in forward and reverse modes, further increasing circuit complexity and component cost.        